Enderman make the stare sound when losing hostility because of daytime

I was fighting an Enderman during the day when he suddenly lost interest and teleported away. He had turned neutral and then made the stare growl sound.

To reproduce

1. Be in Survival mode
2. Summon an Enderman
3. Look at its head
   → Scary sound
4. Wait for the sound to end
5. Look at the ground and run away from the enderman (in order for the enderman to calm down)
6. The enderman becomes neutral again
   → Another scary sound

Video

Minecraft 21w18a - Singleplayer 2021-05-06 17-39-56.mp4